Transport system: WAEC Biology Past Questions and Answers

What the WAEC syllabus covers in Transport system

Our summary: Why organisms need transport, how blood and lymph move materials in animals, and how water, minerals and food move in plants.

• Need for transport: surface area/volume ratio; substances have to move greater distances (Source of materials and forms in which they are transported and where they are transported to should be studied. Media of transport: cytoplasm in cells, cell sap or latex in most plants and body fluid in invertebrates.)
• Transport in animals: structure of the heart, arteries, veins and capillaries; composition and function of blood and lymph; materials for transport: excretory products, gases, digested food, and other nutrients (Candidates should be familiar with the general circulatory system. Open circulatory systems in invertebrates. The names of the blood vessels responsible for transporting excretory products, gases, digested food and other nutrients should be mentioned.)
• Transport in plants: uptake and movement of water and mineral salts in plants (Description of uptake of water and mineral salts from the soil into a plant. Movement of water and mineral salts through the plant. Experiments using eosin solution to show water and mineral salts uptake.)
• Translocation (Movement of organic materials from leaves to roots. Basic theories (pressure flow hypothesis and cytoplasmic streaming) underlying translocation. Ringing experiment to demonstrate that transport of synthesized organic nutrients occurs through the phloem.)
• Transpiration (Advantages and disadvantages of transpiration. Types of transpiration. Environmental factors affecting transpiration. Determination of the rate of transpiration.)
• Movement of water to the apex of trees and herbs (Physiological factors affecting the rise of water in the xylem: root pressure, transpiration, cohesion-tension mechanism, adhesion, water potential gradient. Experiments to measure the rate of transpiration.)

Syllabus content © The West African Examinations Council (WASSCE (harmonised West African syllabus)).